TYK2 and viral load: - AR complete TYK2 deficiency (with or without TYK2 expression) (131, 132, 134–136): Characterized by MSMD (and more rarely tuberculosis) and/or viral diseases due to an impaired response to IL-12, IL-23 (poor IFN-γ underlies mycobacterial diseases), IFN-α (viral diseases), and IL-10 signaling.